Multiple timers for request to send and clear to send communications

ABSTRACT

Techniques for procedures using request to send/clear to send (RTS/CTS) procedures and multiple timers are described. A RTS/CTS procedure using multiple timers may use a first timer and a second timer. The first timer may be associated with a duration to transmit and receive a request to send (RTS) message and a clear to send (CTS) message. The second timer may be associated with a duration to transmit a data message. A network device may transmit a RTS message to request communication resources to transmit data. If the CTS message is not received prior to the expiration of the first timer, neighboring network devices may determine that the communication resources were not allocated and may attempt to request the newly available resources. If a CTS message is received, the network device may communicate the second timer data to the neighboring network devices in a variety of ways.

CROSS REFERENCES

The present Application for Patent is a continuation of U.S. patentapplication Ser. No. 15/427,839 by ISLAM, et al., entitled “ MULTIPLETIMERS FOR REQUEST TO SEND AND CLEAR TO SEND COMMUNICATIONS” filed Feb.8, 2017, which claims priority to U.S. Provisional Patent ApplicationNo. 62/402,829 by ISLAM, et al., entitled “MULTIPLE TIMERS FOR REQUESTTO SEND AND CLEAR TO SEND COMMUNICATIONS,” filed Sep. 30, 2016, assignedto the assignee hereof, and each of which is expressly incorporated byreference herein.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to multiple timers for request to send and clear to sendcommunications.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems, (e.g., a Long Term Evolution(LTE) system). A wireless multiple-access communications system mayinclude a number of base stations, each simultaneously supportingcommunication for multiple communication devices, which may be otherwiseknown as user equipment (UE).

Some communication systems may allocate communication resources using acontention-based system. For example, when communication resourcesbecome available, one or more devices may request to use the availableresources by transmitting a request to send message to another device.The other device may grant communication resources to one of therequesting devices and may transmit a clear to send message. Some timersused to avoid collisions in such a contention-based system, however, maycreate inefficient allocations of communication resources.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support multiple timers for request to send andclear to send communications. Techniques for a procedure using multipletimers and a request to send (RTS)/clear to send (CTS) procedure aredescribed. A procedure using RTS/CTS and multiple timers may use a firsttimer and a second timer. The first timer may be associated with aduration to transmit a RTS message and receive a CTS message, amongother operations. The second timer may be associated with a duration totransmit a data message, among other operations. A network device maytransmit a RTS message to request communication resources. If the CTSmessage is not received before the expiration of the first timer,neighboring network devices may determine that the communicationresources were not allocated and may attempt to request the newlyavailable resources and/or may initiate one or more transmission. If aCTS message is received, the network device may communicate data relatedto a second timer to one or more other devices in a variety of ways.

A method of wireless communication is described. The method may includedetermining a first timer based at least in part on a duration fortransmitting a first request to send (RTS) message and a duration forreceiving a clear to send (CTS) message, transmitting the first RTSmessage associated with the first timer, receiving the CTS messagebefore an expiration of the first timer based at least in part on thefirst RTS message, and transmitting, in response to receiving the CTSmessage, a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor the UE.

An apparatus for wireless communication is described. The apparatus mayinclude means for determining a first timer based at least in part on aduration for transmitting a first RTS message and a duration forreceiving a CTS message, means for transmitting the first RTS messageassociated with the first timer, means for receiving the CTS messagebefore an expiration of the first timer based at least in part on thefirst RTS message, and means for transmitting, in response to receivingthe CTS message, a data message having a second timer different from thefirst timer, the data message associated with a data transmissionopportunity for the UE.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to determine a first timer based atleast in part on a duration for transmitting a first RTS message and aduration for receiving a CTS message, transmit the first RTS messageassociated with the first timer, receive the CTS message before anexpiration of the first timer based at least in part on the first RTSmessage, and transmit, in response to receiving the CTS message, a datamessage having a second timer different from the first timer, the datamessage associated with a data transmission opportunity for the UE.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to determine a first timerbased at least in part on a duration for transmitting a first RTSmessage and a duration for receiving a CTS message, transmit the firstRTS message associated with the first timer, receive the CTS messagebefore an expiration of the first timer based at least in part on thefirst RTS message, and transmit, in response to receiving the CTSmessage, a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor the UE.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the second timer comprises anetwork allocation vector (NAV) timer.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the data message comprises asecond RTS message.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the second timer may have alonger duration than the first timer.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the data message comprisesinformation indicating a duration of the second timer.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying a duration of the datatransmission opportunity for the UE. Some examples of the method,apparatus, and non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions fordetermining the second timer based at least in part on the duration ofthe data transmission opportunity.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for establishing a directionalcommunication link with a base station, the directional communicationlink using a first set of communication resources.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for measuring a channel conditionassociated with the directional communication link, wherein transmittingthe first RTS message may be based at least in part on the measuredchannel condition associated with the directional communication link.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying that a radio linkfailure event associated with the directional communication link mayhave occurred, wherein transmitting the first RTS message may be basedat least in part on identifying that the radio link failure eventoccurred.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, transmitting the first RTSmessage further comprises: transmitting the first RTS message using asecond set of communication resources different than the first set ofcommunication resources.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first set of communicationresources comprise a first radio access technology (RAT). In someexamples of the method, apparatus, and non-transitory computer-readablemedium described above, the second set of communication resourcescomprise a second RAT different from the first RAT.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the first RTS message, the CTSmessage, and the data message may be transmitted using a cellular radioaccess technology.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for comparing a duration of the datamessage to a threshold. Some examples of the method, apparatus, andnon-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for determining thesecond timer based at least in part on the duration of the data messageexceeding the threshold.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining a size of dataassociated with the data message, if the size may be less than athreshold then: determining the first timer based at least in part onthe duration for transmitting the first RTS message, the duration forreceiving the CTS message, and the duration for transmitting the datamessage. Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the first RTS messageassociated with the first timer. Some examples of the method, apparatus,and non-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for transmitting, inresponse to receiving the CTS message, the data message; and. Someexamples of the method, apparatus, and non-transitory computer-readablemedium described above may further include processes, features, means,or instructions for if the size may be greater than the threshold then:determining the first timer based at least in part on the duration fortransmitting the first RTS message and the duration for receiving theCTS message. Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for transmitting the first RTS messageassociated with the first timer. Some examples of the method, apparatus,and non-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for receiving theCTS message before the expiration of the first timer. Some examples ofthe method, apparatus, and non-transitory computer-readable mediumdescribed above may further include processes, features, means, orinstructions for transmitting, in response to receiving the CTS message,the data message having the second timer different from the first timer.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying a size of dataassociated with the data message. Some examples of the method,apparatus, and non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions forcomparing the size to a threshold, wherein the first timer, or thesecond timer, or both may be based at least in part on the comparison.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for setting the second timer based atleast in part on the size being less than the threshold.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for setting the second timer based atleast in part on the size being greater than the threshold.

Some examples of the apparatus described above may further include anantenna, or a display, or a user interface, or a combination thereof.

A method of wireless communication is described. The method may includereceiving a RTS message having a first timer based at least in part on aduration for receiving the RTS message and a duration for transmitting aCTS message, transmitting the CTS message before an expiration of thefirst timer based at least in part on the RTS message, and receiving adata message having a second timer different from the first timer, thedata message associated with a data transmission opportunity for a userequipment (UE).

An apparatus for wireless communication is described. The apparatus mayinclude means for receiving a RTS message having a first timer based atleast in part on a duration for receiving the RTS message and a durationfor transmitting a CTS message, means for transmitting the CTS messagebefore an expiration of the first timer based at least in part on theRTS message, and means for receiving a data message having a secondtimer different from the first timer, the data message associated with adata transmission opportunity for a UE.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive a RTS message having afirst timer based at least in part on a duration for receiving the RTSmessage and a duration for transmitting a CTS message, transmit the CTSmessage before an expiration of the first timer based at least in parton the RTS message, and receive a data message having a second timerdifferent from the first timer, the data message associated with a datatransmission opportunity for a UE.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to receive a RTS messagehaving a first timer based at least in part on a duration for receivingthe RTS message and a duration for transmitting a CTS message, transmitthe CTS message before an expiration of the first timer based at leastin part on the RTS message, and receive a data message having a secondtimer different from the first timer, the data message associated with adata transmission opportunity for a UE.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the second timer comprises aNAV timer.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for receiving the data message duringthe second timer.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, at least a part of the datamessage may be received from the UE, in response to the second RTSmessage, before transmitting a second CTS message.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the data message comprisesinformation indicating a duration of the second timer.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for remaining idle during the indicatedduration of the second timer in response to receiving the data message.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the second timer may be longerthan the first timer.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the data message comprises asecond RTS message.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for establishing a directionalcommunication link with the UE, the directional communication link usinga first set of communication resources, wherein the RTS message may bereceived using a second set of communication resources different thanthe first set of communication resources.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining whether a keepalivemessage may have been received from the UE, wherein transmitting the CTSmessage may be based at least in part on the keepalive message.

Some examples of the apparatus described above may further include anantenna, or a display, or a user interface, or a combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationthat supports multiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 2 illustrates an example of a block diagram of a wirelesscommunication system that supports multiple timers used for request tosend and clear to send communications in accordance with various aspectsof the present disclosure.

FIG. 3 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 4 illustrates an example of a packet structure that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 5 illustrates an example of a computing environment that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 6 illustrates an example of a timeline that supports multipletimers used for request to send and clear to send communications inaccordance with various aspects of the present disclosure.

FIG. 7 illustrates an example of a packet structure that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 8 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 9 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 10 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 11 illustrates an example of a packet structure that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 12 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 13 illustrates an example of a packet structure that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 14 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 15 illustrates an example of a packet structure that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 16 illustrates an example of a communication scheme that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIGS. 17 through 19 show block diagrams of a device that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 20 illustrates a block diagram of a system including a UE thatsupports multiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIGS. 21 through 23 show block diagrams of a device that supportsmultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIG. 24 illustrates a block diagram of a system including a base stationthat supports multiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure.

FIGS. 25 through 28 illustrate methods for multiple timers used forrequest to send and clear to send communications in accordance withvarious aspects of the present disclosure.

DETAILED DESCRIPTION

Some techniques using RTS/CTS procedures may use a single timer and maycause inadequate or inefficient use of some communication resources insome instances. Techniques described in present disclosure relate to aRTS/CTS procedure that includes multiple timers to more efficientlyallocate communication resources.

In a RTS/CTS procedure, a UE may transmit a RTS message to a basestation to request communication resources to transmit data to anintended recipient. The base station may transmit a CTS messageallocating some communication resources to the UE. To avoid collisionsbetween different UEs trying to use communication resources, the RTSmessage may include timer data that indicates a duration associated withthe RTS and a related CTS. Neighboring UEs that receive the RTS messagefrom the UE may silence communications during a requested duration basedat least in part on the timer data included in the RTS message.

In other RTS/CTS procedures the timer data may include a duration thatspans at least from the transmission/reception of the RTS message to anexpected conclusion of the transmission/reception of the data message.In some instances, however, the requesting device (e.g., a UE) does notreceive a CTS message. Because the neighboring UEs have already silencedtheir communications for an extended duration that expected the exchangeof data, the resources that the UE initially requested may gounused—creating inefficiency.

The present disclosure describes techniques based on a procedure (e.g.,a RTS/CTS-based procedure) using multiple timers. For example, a RTS/CTSprocedure may use two timers instead of one. The first timer may beassociated with a duration to transmit and receive the RTS message andthe CTS message, respectively. The second timer may be associated with aduration to transmit a data message, among other information. If the CTSmessage is not received before the expiration of the first timer,neighboring UEs may determine that the requesting UE was not grantedaccess to the requested communication resources. The communicationresources—including those that may have otherwise been allocated for oneor more data transmissions—are available to be used by the neighboringUEs. In some examples, the neighboring UEs may generate and transmittheir own RTS messages requesting the newly available resources or insome instances may initiate one or more transmissions.

In the event that the requesting UE is granted permission to transmitits data, the UE may communicate the data to the another device or otherdevices in a variety of ways. In some examples, the data related to orincluded in the second timer may be included in the data message itself.The neighboring UEs may silence their communications during the durationof the second timer. The use of multiple timers may allow a RTS/CTSprocedure to more efficiently allocate communication resources andprevent allocating resources unnecessarily.

Aspects of the disclosure are initially described in the context of awireless communications system. Aspects of the disclosure are furtherillustrated by and described with reference to packet structures andcommunication schemes that relate to multiple timers used for request tosend and clear to send communications. Aspects of the disclosure arefurther illustrated by and described with reference to apparatusdiagrams, system diagrams, and flowcharts that relate to multiple timersfor request to send and clear to send communications.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with various aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a LTE (or LTE-Advanced) network. The UEs may contend foraccess to communication resources using a RTS/CTS procedure. A RTS/CTSprocedure may use multiple timers to more efficiently allocatecommunication resources between UEs contending for those resources. Abase station may generate and transmit CTS messages based at least inpart on received RTS messages. If the CTS message is not received priorto an expiration of a first timer, other UEs may attempt to request thecommunication resources not granted to the sender of the RTS request.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Each base station 105 may providecommunication coverage for a respective geographic coverage area 110.Communication links 125 shown in wireless communications system 100 mayinclude uplink (UL) transmissions from a UE 115 to a base station 105,or downlink (DL) transmissions, from a base station 105 to a UE 115. UEs115 may be dispersed throughout the wireless communications system 100,and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile station, a subscriber station, a mobile unit, asubscriber unit, a wireless unit, a remote unit, a mobile device, awireless device, a wireless communications device, a remote device, amobile subscriber station, an access terminal, a mobile terminal, awireless terminal, a remote terminal, a handset, a user agent, a mobileclient, a client, or some other suitable terminology. A UE 115 may alsobe a cellular phone, a personal digital assistant (PDA), a wirelessmodem, a wireless communication device, a handheld device, a tabletcomputer, a laptop computer, a cordless phone, a personal electronicdevice, a handheld device, a personal computer, a wireless local loop(WLL) station, an Internet of things (IoT) device, an Internet ofEverything (IoE) device, a machine type communication (MTC) device, anappliance, an automobile, or the like. In some examples, the UE 115 mayinclude an antenna, or a display, or a user interface, or a combinationthereof.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., S1). Base stations 105 maycommunicate with one another over backhaul links 134 (e.g., X2) eitherdirectly or indirectly (e.g., through core network 130). Base stations105 may perform radio configuration and scheduling for communicationwith UEs 115, or may operate under the control of a base stationcontroller (not shown). In some examples, base stations 105 may be macrocells, small cells, hot spots, or the like. Base stations 105 may alsobe referred to as eNodeBs (eNBs) 105.

FIG. 2 illustrates an example of a wireless communications system 200for multiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. The wireless communications system 200 may be an example ofthe wireless communications system 100 discussed with reference toFIG. 1. The wireless communications system 200 may include a basestation 105-a, a UE 115-a, and a UEs 115-b. A coverage area 110-a may bedefined for the base station 105-a. The UE 115-a may refer to atransmitting UE that is attempting to secure available resources via aRTS message. The UE 115-b may refer to a receiving UE that receives theRTS message from the UE 115-a. In some examples, the UE 115-b may be thetransmitting UE and the UE 115-a may be the receiving UE. While two UEs115 are shown, the wireless communications system 200 may includeadditional UEs 115, including UEs 115 transmitting RTS messages and UEs115 receiving RTS messages. In some examples, the same UE 115 may bothtransmit and receive RTS messages. The base station 105-a may be anexample of the base stations 105 described with reference to FIG. 1. TheUEs 115-a and 115-b may be examples of the UEs 115 described withreference to FIG. 1.

In some examples, the base station 105-a may communicate with the UE115-a or the UE 115-b via directional communication links 205 (sometimesreferred to as directional wireless beams or directional beams). Thedirectional communication links 205 may be pointed in a specificdirection and provide high-bandwidth links between the base station105-a and the UE 115-a. Signal processing techniques, such asbeamforming, may be used to coherently combine energy to form thedirectional communication links 205. Wireless communication linksachieved through beamforming may be associated with narrow beams (e.g.,“pencil beams”) that are highly directional, minimize inter-linkinterference, and provide high-bandwidth links between wireless nodes(e.g., base stations, access nodes, UEs).

In some examples, the base station 105-a may operate in millimeter wave(mmW) frequency ranges, e.g., 28 GHz, 40 GHz, 60 GHz. In some examples,the directional communication links 205 are transmitted usingfrequencies greater than 6 GHz. Wireless communication at thesefrequencies may be associated with increased signal attenuation, e.g.,path loss, which may be influenced by various factors, such astemperature, barometric pressure, diffraction. Dynamic beam-steering andbeam-search capabilities may additionally or alternatively support, forexample, discovery, link establishment, and beam refinement in thepresence of dynamic shadowing and Rayleigh fading. Additionally,communication in such mmW systems may be time division multiplexed,where a transmission may be directed to one wireless device at a timedue to the directionality of the transmitted signal.

Each directional communication link 205 may have beam characteristicssuch as a width 210 and a direction 215 (e.g., an absolute directionbased on a coordinate system such as compass directions or a relativedirection) where the directional communication link 205 is pointed. Thewidth 210 for each directional communication link 205 may be different(e.g., compare the width 210-1 of the directional communication link205-1 to the width 210-3 of the directional communication link 205-3).The width 210 of the directional communication link 205 may be expressedin degrees. The width 210 of the directional communication link 205 maybe expressed in other ways such as a dimension (e.g., a distance) of thebeam at a given point. The width 210 may be related to the size of thephased array antenna used to generate the directional communication link205. Different widths 210 may be used by the base station 105-a indifferent scenarios.

For example, a first message may be transmitted/received using adirectional wireless beam having a first beam width, while a secondmessage may be transmitted/received using a directional wireless beamhaving a second beam width different than the first beam width. The basestation 105-a may generate any number of directional communication links205 (e.g., directional communication link 205-N). The directionalcommunication links 205 generated by the base station 105-a may bepointed at any geographic location.

The direction 215 may refer to a target of the directional communicationlink 205. The direction 215 of the directional transmission may be alocation of a UE 115-a. The direction 215 may be any location in athree-dimensional space. For example, the direction 215 may include apitch parameter indicative of a vertical pitch of the directionalcommunication link 205 and a position vector indicative of a directionthat the directional communication link 205 is pointing (e.g., adirection on a compass).

FIG. 3 illustrates an example of a communication scheme 300 for a singletimer used for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 300 may include a RTS/CTS procedure. The RTS/CTSprocedure may be initiated based at least in part on an device or entity(e.g., UE 115-a) determining that it has data waiting to be sent to adifferent device (e.g., base station 105-a). A RTS/CTS procedure may beused as part of a contention-based radio access technology (RAT) (e.g.,Wi-Fi) to reduce communication collisions. Such collisions may preventdata from being received by its intended recipient. In some examples, aRTS/CTS procedure may be implemented using a non-contention based RATssuch as 3G, LTE, 5G, or others. In the illustrative example of FIG. 3,the UE 115-a is transmitting a RTS message 305 as part of the RTS/CTSprocedure. It should be appreciated that the RTS/CTS procedure may beimplemented by any number of devices in a wireless communication system(e.g., base station 105-a, UE 115-b).

A wireless communications system 200 that uses directional communicationlinks 205 may use the RTS/CTS procedure to re-establish a communicationlink that has been unexpectedly terminated. Directional communicationlinks 205 serve a limited geographic area. UEs 115 are able to movethrough the wireless communications system 200. In some instances, theUEs 115 may move out of the limited geographic area served by adirectional communication link 205. In such an event, the directionalcommunication link 205 between the base station 105 and the UE 115 maybe severed. The directional communication links 205 may use a particularset of communications resources (e.g., frames, radio frequency spectrumband).

Upon determining that a directional communication link 205 has beenterminated prematurely, the UE 115-a may begin using a dedicated setcommunication resources to re-establish the directional communicationlink 205. The dedicated set of communication resources may be differentthan the communication resources used by the directional communicationlink. In addition, the dedicated set of communication resources may usea RTS/CTS procedure to avoid communication collisions. In some examples,the dedicated set of communication resources are implemented using adifferent RAT than what is used to implement the communication resourcesof the directional communication link 205.

It should be appreciated that the RTS/CTS procedure may be implementedin other ways besides a set of dedicated communication resources. Forexample, a UE 115-a may use the RTS/CTS procedure before transmittingdata to the base station 105-a using the directional communication link205-1. The RTS/CTS procedure may be implemented in other contexts aswell. In this manner, the UE 115-a may use the dedicated set ofcommunication of resources and the RTS/CTS procedure to re-establish adirectional communication link 205 with the base station 105-a.

The RTS/CTS procedure with a single timer may include a RTS message 305,a CTS message 310, and a data message 315. The UE 115-a or the UE 115-bmay perform the RTS/CTS procedure to obtain permission to transmit data.

The RTS message 305 is configured to request communication resourcesfrom the base station 105-a. The communication resources may define atransmission opportunity for the UE 115-a. In a contention-based RAT, aUE 115-a contends with other UEs (e.g., UE 115-b) to secure transmissionopportunities. As soon as a communication resources become available,the UE 115-a and any other UEs (e.g., UE 115-b) with data to betransmitted may attempt to secure the newly available resources using aRTS message 305. The base station 105 may determine which RTS message305 will receive the available communication resources.

The RTS message 305 may be broadcast by the UE 115-a. As such, the RTSmessage 305 transmitted by the UE 115-a may be received by the basestation 105-a, the UE 115-b, or any other network entities that may bewithin range of the UE 115-a. A purpose of the RTS message 305 may be torequest communication resources from the base station 105-a. Anotherpurpose of the RTS message 305 may be to communicate information to theother UEs (e.g., UE 115-b) about the pending request for communicationresources. For example, the RTS message 305 may include timer data 405that indicates to the other UEs that they should refrain fromtransmitting for a period of time. As will be discussed in more detailbelow, when the UE 115-b receives the RTS message 305, the UE 115-b mayset a timer based on the timer data 405 included in the RTS message 305.

The CTS message 310 may be generated by the base station 105-a inresponse to receiving the RTS message 305. The CTS message 310 isconfigured to assign available resources to the UE that sent the RTSmessage 305 (e.g., UE 115-a). The CTS message 310 may contain a thirdtimer data that instructs other UEs receiving the CTS message to refrainfrom transmitting until the end of the period of time determined atleast in part by the timer data 405. After receiving one or more RTSmessages 305, the base station 105-a may determine which request may begranted and may generate a CTS message 310 for that granted request.

The CTS message 310 may be intended for the UE that is having itsrequest for communication resources granted (e.g., UE 115-a). The basestation 105-a may broadcast the CTS message 310. As such, the UE 115-badditionally or alternatively may receive the CTS message 310. The UE115-b may not be a primary intended recipient for the CTS message 310,the other UE 115-b may still use the CTS message 310 to perform somefunctions. If a third UE 115-c (not shown) receives CTS message 310 butdoes not receive the RTS message 305, the third UE 115-c may refrainfrom transmitting during the transmit opportunity granted to UE 115-ausing the third timer information and the instruction found in the CTSmessage 310.

The UE 115-a may transmit a data message 315 in response to receiving aCTS message 310. The data message 315 may include the data 415 waitingto be transmitted to the base station 105-a. The data message 315 may betransmitted during the transmission opportunity indicated in the CTSmessage 310. The UE 115-b may be capable of receiving the broadcasteddata message 315.

FIG. 4 illustrates an example of a packet structure 400 for messagesincluded in a RTS/CTS procedure with a single timer in accordance withvarious aspects of the present disclosure. The packet structure 400includes the packet structure for the RTS message 305, the CTS message310, and the data message 315.

The RTS message 305 may include timer data 405 and other data 410. Thetimer data 405 may be configured to indicate a duration of a timer to beinitiated by the UE 115-b upon receiving a RTS message 305. The RTSmessage 305 may include a number of bits. Portions of the RTS message305 may be dedicated to conveying specific types of data. For example, aRTS message 305 may include a frame control portion, a timer dataportion, a receiver address portion, a transmitter address portion, aframe check sequence portion, or any combinations thereof. The otherdata 410 in the RTS message 305 may include any data not associated witha timer.

The timer data 405 may include a network allocation vector (NAV) timer.A NAV timer indicates how long the UE 115-b should be silent in responseto receiving the RTS message 305 transmitted by the UE 115-a. The NAVtimer may indicate a duration that extends from the reception of the RTSmessage 305 by the UE 115-b to the conclusion of the data message 315.However, in some instances, the UE 115-a that transmits the RTS message305 may not receive a CTS message 310 from the base station 105-a inresponse. In those instances, the UE 115-a will not transmit the datamessage 315 because the UE 115-a was not cleared to transmit the datamessage 315. Because the NAV timer indicates that the UE 115-b should besilent for a duration that concludes with the expected duration of thedata message 315, the UE 115-b may not attempt to use the communicationresources not being used by the UE 115-a. As such, availablecommunication resources may go unused leading to an inefficient use ofthose communication resources.

The CTS message 310 may include a number of bits. Portions of the CTSmessage 310 may be dedicated to conveying specific types of data. Forexample, a CTS message 310 may include a frame control portion, a timerdata portion, a receiver address portion, a transmitter address portion,a frame check sequence portion, or any combinations thereof. The CTSmessage 310 may additionally or alternatively include a duration of thetransmission opportunity being granted to the UE 115-a. The informationin the CTS message 310 on the duration of the transmission opportunitybeing granted to UE 115-a may be used by any other UEs to refrain fromtransmitting during UE 115-a's transmission opportunity.

The data message 315 may include data 415. The data 415 may be intendedfor a particular recipient (e.g., base station 105-a). A duration of thedata 415 may vary.

FIG. 5 illustrates an example of a computing environment 500 formultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. To address potentially inefficient uses of communicationresources in a RTS/CTS procedure that has a single timer, a RTS/CTSmessage using multiple timers is described herein. To implement amultiple timer RTS/CTS procedure, a UE 115 (e.g., UE 115-a or UE 115-b)may include a first timer 505 and a second timer 510. The first timer505 may be associated with first timer data included in the timer data705. The second timer 510 may be associated with second timer dataincluded in the timer data 710. Using two timers allows the UE 115-b toattempt to use resources that were not cleared to be used. For example,if the UE 115-a does not receive a CTS message 310-a in response to itsRTS message 305-a, the UE 115-b may send its own RTS message requestingto use the newly available resources prior to the expiration of atraditional NAV timer.

Upon receiving the RTS message 305, the UE 115-b may determine durationsincluded in the timer data. Using those durations, the UE 115-b mayinitiate the first timer 505. The first timer 505 is set to a durationvalue. The first timer 505 may decrement it's value until it reacheszero. At zero, the UE 115-b may determine that it can send its own RTSmessage requesting resources. If the UE 115-b receives a different RTSmessage 305-a prior to the expiration of the previous timer, the UE115-b may reset its timer based on the duration included in thedifferent RTS message 305-a.

In the multiple timer RTS/CTS procedure discussed herein, the firsttimer 505 may be based at least in part on a duration associated withthe RTS message 305 and the CTS message 310 and the second timer 510 maybe based at least in part on a duration associated with the data message315. In this manner, a UE 115 may be configured to react to changingnetwork conditions and request communication resources in a moreefficient manner than using a single timer, such as a NAV timer. In someexamples, the UE 115-a may include additional timers (e.g., threetimers, four timers, five timers).

FIG. 6 illustrates an example of a communications timeline 600 formultiple timers used for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. The communications timeline 600 may indicate durationsassociated with a multiple timer RTS/CTS procedure. The durationdescribed herein may be used to determine timer data associated with thefirst timer 505 or timer data associated with the second timer 510. Asused herein, a duration may refer to a period of time. For example, aduration may refer to a period of time it takes to transmit a message.In another example, a duration may refer to a period of time it takes toperform an operation. In other examples, a duration may refer to aperiod of time taken between other operations or transmission.

The communications timeline 600 shows that first a RTS message 305 maybe transmitted, next a CTS message 310 may be transmitted, and finally adata message 315 may be transmitted. A gap 605 may exist between theconclusion of the RTS message 305 transmission and the beginning of theCTS message 310 transmission. The gap 605 may have a duration. The gap605 may exist because an entity that receives the RTS message 305 mayrequire time to decode the RTS message 305, make determinations,generate a CTS message 310, or transmit the CTS message 310. A similargap 610 may exist between the conclusion of the CTS message 310transmission and the beginning of the data message 315 transmission. Thegap 610 may have a duration. The gap 610 may exist because an entitythat receives the CTS message 310 may require time to decode the CTSmessage 310, make determinations, generate a data message 315, ortransmit the data message 315.

The RTS message 305 may take a duration 615 to transmit. The duration615 may extend from the beginning of a RTS message transmission to theconclusion of the RTS message transmission. The CTS message 310 maketake a duration 620. The duration 620 may extend from the beginning of aCTS message transmission to the conclusion of the CTS messagetransmission. The duration 615 may be different than the duration 620.In some examples, the duration 615 is the same as the duration 620. Thedata message 315 may take a duration 625. The duration 625 may extendfrom an expected beginning of a data message transmission to an expectedconclusion of a data message transmission. The duration 625 of the datamessage 315 may be based at least in part on a transmission opportunityindicated in the CTS message 310. In some examples, the duration 625 maybe based at least in part on a duration associated with the data 415being transmitted in the data message 315.

Other durations may be defined based at least in part on the RTS/CTSprocedure. For example, a duration 630 may be defined between anexpected beginning of a RTS message transmission and an expectedconclusion of a CTS message transmission. A duration 635 may be extendbetween an expected beginning of a RTS message transmission to anexpected beginning of a data message transmission. A duration 640 mayextend from an expected conclusion of a RTS message transmission to anexpected conclusion of a CTS message transmission. A duration 645 mayextend from an expected conclusion of a RTS message transmission to anexpected beginning of a data message transmissionspe A duration 650 mayextend from an expected conclusion of a CTS message transmission to anexpected conclusion of a data message transmission. A duration 655 mayextend from an expected beginning of a CTS message transmission to anexpected conclusion of a data message transmission. A duration 660 mayextend from an expected conclusion of a RTS message transmission to anexpected conclusion of a data message transmission. A duration 665 mayextend from a beginning of a RTS message transmission to a conclusion ofa data message transmission. A duration 670 may account for a portion ofthe data message 315.

In some examples, the duration 670 may be based at least in part on aduration of the data 415 in the data message 315. A duration 675 mayextend from an expected conclusion of the RTS message 305 to an expectedbeginning of the data 415 portion of the data message 315. In someexamples, the duration 675 may extend from an expected conclusion of theRTS message 305 to an expected conclusion of a transmission that includethe second timer data 710.

Timer data used in the RTS/CTS procedure may be based at least in parton any of the durations described above, on other durations that may bepresent in a RTS/CTS procedure, or any combinations thereof. Techniquesare described herein to use multiple timers as part of a RTS/CTSprocedure. In a single RTS/CTS procedure, timer data may be based atleast in part on multiple durations.

Durations used by timer data in the RTS/CTS procedure to determine timerdata 405 may additionally or alternatively include an error margin 680.For example, timer data 405 may be based at least in part on theduration 640 and an error margin 680. The error margin 680 may refer toa variable duration that is added to a more defined duration associatedwith the RTS/CTS procedure when used in timer data. In some instances,an actual arrival time of a message may vary from its expected arrivaltime. The error margin 680 is a duration of time configured to prevent atimer of the UE 115-b (e.g., first timer 505 or second timer 510) fromexpiring prematurely. In such a situation, the UE 115-b may incorrectlydetermine that resources are available when, in fact, the UE 115-a maybe transmitting the data message 315 based at least in part on alate-arriving CTS message 310. In these instances, the UE 115-b maytransmit its own RTS message that collides with the data message 315being transmitted by the UE 115-a.

FIG. 7 illustrates an example of a packet structure Error! Referencesource not found.00 using multiple timers for request to send and clearto send communications in accordance with various aspects of the presentdisclosure. The packet structure 700 includes a RTS message 305-a, a CTSmessage 310-a, and a data message 315-a. The RTS message 305-a may be anexample of the RTS message 305 described with reference to FIGS. 3-6.The CTS message 310-a may be an example of the CTS message 310 describedwith reference to FIGS. 3-6. The CTS message 310 may contain a thirdtimer data (not shown) determined by the base station 105-b thatinstructs other UEs receiving the CTS message to refrain fromtransmitting until the expected end of the transmission of the datamessage 315-a. The expected end of the data message 315-a transmissionis determined by the base station 105-b based on the amount of data, thecurrent uplink transmission rate, etc., as conveyed in the other data410-a field of the RTS message 305 from the UE 115-a. The data message315-a may be an example of the data message 315 described with referenceto FIGS. 3-6.

The RTS message 305-a may include other data 410-a and first timer data705. The other data 410-a may be an example of other data 410 describedwith reference to FIG. 4. The first timer data 705 may include aduration associated with the RTS message 305-a and the CTS message310-a. In particular, the duration indicated in the first timer data 705may relate to a duration associated with the RTS message 305-a and aduration associated with the CTS message 310-a. The duration included inthe first timer data 705 may be the duration 640 with or without anerror margin 680. The duration 640 may extend from the reception of theRTS message 305-a by the UE 115-b to an expected conclusion of a CTSmessage 310. In some examples, if the CTS message 310-a is not received,the first timer 505 based on the first timer data 705 may expire asdiscussed in more detail in FIG. 9.

In some examples, the duration included in the first timer data 705 maybe duration 615, duration 620, duration 630, duration 635, duration 645,or duration 675. The duration included in the first timer data 705 mayadditionally or alternatively include an error margin 680. In otherexamples, the duration included in the first timer data 705 may beduration 650, 655, 660, 665, or 670 with or without an error margin 680.In other examples, the duration included in the first timer data 705 maybe other durations related to a RTS/CTS procedure.

The data message 315-a may include data 415-a and second timer data 710.The data 415-a may be an example of the data 415 described withreference to FIGS. 3 and 4. The second timer data 710 may be based atleast in part on the first timer data 705. In this manner the firsttimer data 705 and the second timer data 710 may cooperate to define aduration of a RTS/CTS procedure. The second timer data 710 may include aduration associated with the data message 315. The second timer data 710may include a duration associated with the data 415-a portion of thedata message, such as duration 670. For example, the duration includedin the second timer data 710 may be the duration 670 with or without anerror margin 680. The duration included in the second timer data 710 mayextend from an expected beginning of the data 415-a portion of the datamessage 315-a to an expected conclusion of the data 415-a portion of thedata message 315-a.

In some examples, the duration included in the first timer data 705 maybe duration 615, duration 620, duration 630, duration 635, duration 640,duration 645, duration 650, duration 655, duration 660, duration 665, orduration 675. The duration included in the second timer data 710 mayadditionally or alternatively include an error margin 680. In otherexamples, the duration included in the second timer data 710 may beother durations related to a RTS/CTS procedure.

FIG. 8 illustrates an example of a communication scheme 800 usingmultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 800 may be an example of how the packet structures700 described with relation to FIG. 7 may be communicated during aRTS/CTS procedure.

At block 805, the UE 115-a may determine first timer data 705 having aduration. As discussed in the present disclosure, the first timer data705 may include a duration associated with an expected arrival time ofthe CTS message 310-a. Once the first timer data 705 is determined, theUE 115-a may generate the RTS message 305-a that includes the firsttimer data 705. The UE 115-a may transmit the RTS message 305-a to thebase station 105-a and the UE 115-b. The duration in the first timerdata 705 may be determined such that other UEs (e.g., UE 115-b) mayrequest to use resources if the UE 115-a does not receive a CTS message310-a from the base station 105-a prior to the expiration of the firsttimer 505.

At block 810, the base station 105-a may determine whether to send a CTSmessage 310-a in response to receiving the RTS message 305-a. The basestation 105-a may receive multiple RTS messages at a timer. The basestation 105-a may generate the CTS message 310-a based at least in parton information included in the RTS message 305-a. In some examples, thebase station 105-a may determine a duration included in the first timerdata 705. The base station 105-a may transmit a CTS message before theduration in the first timer data 705 expires. In some examples, the CTSmessage 310-a may include data indicating a duration of the transmissionopportunity allocated to be used by the UE 115-a.

At block 815, the UE 115-b may receive the RTS message 305-a. Uponreceiving the RTS message 305-a, the UE 115-b may initiate a first timer505 based at least in part on the duration included in the first timerdata 705 of the RTS message 305-a. The first timer 505 may decrementuntil it reaches zero. If the UE 115-b receives the CTS message 310-a orreceives a different type of indication that the UE 115-a has receivedthe CTS message 310-a, the UE 115-b may terminate its first timer 505.In some examples, the first timer continues decrementing regardless ofwhether a CTS message 310-a is received. The first timer 505 may bebased at least in part on the first timer data 705 and reception of theRTS message 305-a.

If the UE 115-a receives the CTS message 310-a from the base station105-a, the UE 115-a, at block 820, may determine second timer data 710.The second timer data 710 may include a duration associated with aduration of the transmission opportunity. In some examples, the secondtimer data 710 may include a duration associated with the data message315-a or a data 415-a portion of the data message 315-a. In someexamples, the UE 115-a may determine the second timer data 710 prior toreceiving the CTS message 310-a. For example, the second timer data 710may be determined along with the first timer data 705 at block 805.

The UE 115-a may generate a data message 315-a that includes the secondtimer data 710 and the data 415-a. The UE 115-a may transmit the datamessage 315-a with the second timer data 710 to the base station 105-aand the UE 115-b. In some examples, the second timer data 710 istransmitted and a CTS message is not transmitted in response to thesecond timer data 710.

Upon receiving the data message 315-a, at block 825, the UE 115-b mayset a second timer 510 based at least in part on the duration includedin the second timer data 710 in the data message 315-a. In someexamples, upon initiating the second timer 510, the UE 115-b may ignoreor terminate the first timer 505. In some examples, the second timerdata 710 may be received by the UE 115-b prior to the expiration of thefirst timer 505 based at least in part on the first timer data 705. Thesecond timer 510 may be based at least in part on the second timer data710 and reception of the CTS message 310-a prior to the expiration ofthe first timer 505. The second timer 510 may be based at least in parton the second timer data 710 and reception of the second timer data 710prior to the expiration of the first timer 505.

FIG. 9 illustrates an example of a communication scheme 900 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 900 may indicate operations and procedures thatoccur in a RTS/CTS procedure when the UE 115-b determines that resourceshave become available after the expiration of the first timer.

At block 905, the UE 115-a may determine timer data, such as the firsttimer data 705 and the second timer data 710. Block 905 may be anexample of blocks 805 and 820 described with reference to FIG. 8.

At block 910, the base station 105-a may determine that the UE 115-a isnot clear to send its data 415-a. As such, the base station 105-a maynot transmit the CTS message 310-a. In some examples, the base station105-a may simply ignore the RTS message 305-a upon determining to notfulfill the request.

At block 915, the UE 115-b may set a first timer 505 based at least inpart on the duration included in the first timer data 705 in the RTSmessage 305-a. Block 915 may be an example of block 815 described withreference to FIG. 8.

The UE 115-b may wait for an idle period 920 to determine whether UE115-a is going to be permitted to send its data 415-a. The idle period920 may be based at least in part on the first timer 505 and theduration included in the first timer data 705. The idle period 920 maybe less than an idle period associated with a legacy NAV timer. The idleperiod 920 may be less than an idle period associated with RTS/CTSprocedures that use a single timer.

At block 925, the UE 115-b may determine that the UE 115-a did notreceive permission to use the requested communication resources. The UE115-b may make this determination based at least in part on notreceiving the CTS message 310-a prior to the expiration of the firsttimer 505. The UE 115-b may make this determination based at least inpart on not receiving the second timer data 710 prior to the expirationof the first timer 505. The UE 115-b may make this determination basedat least in part on receiving a separate indication from the basestation 105-a that no CTS message 310-a is forthcoming. As part of thisdetermination, the UE 115-b may determine that the communicationresources once requested to be used by the UE 115-a are now available tobe requested by other devices or entities.

At block 930, the UE 115-b may determine timer data associated with itsown RTS message to be sent to the base station 105-a. The determinationof timer data may be similar to the determinations of timer datadescribed in blocks 805, 820 with reference to FIG. 8. The UE 115-b maytransmit a RTS message 935 that includes first timer data to the basestation 105-a and the UE 115-a. The RTS message 935 may be an example ofRTS message 305-a.

FIG. 10 illustrates an example of a communication scheme 1000 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 1000 may indicate operations and procedures thatoccur in a RTS/CTS procedure to determine whether to initiate a multipletimer RTS/CTS procedure or whether to initiate a single timer RTS/CTSprocedure. As part of these operations and procedures, it mayadditionally or alternatively be determined how many timers to use aspart of a RTS/CTS procedure.

At block 1005, the UE 115-a and the base station 105-a may cooperate toestablish directional communication links, such as a directionalcommunication link 205. The directional communication link may beestablished using a first set of communication resources (e.g., radiofrequency spectrum band resources). The directional communication linkmay be established using a first RAT. The first RAT may include acellular RAT (e.g., 3G, LTE, 4G) or a Wi-Fi RAT (e.g., IEEE 802.11ad).

The directional communication links may include a downlink directionallink, an uplink directional link, or any combination thereof. As part ofestablishing directional communication links, the base station 105-a maydetermine a location of the UE 115-a. In some examples, base stations105 are for example, fixed in a given location while UEs 115 may movethroughout the wireless communication system. To align directionalbeams, the base station 105-a may determine a location of the UE 115-a.The location of the UE 115-a may be determined based at least in part onlocation data generated by the UE 115-a, by a searching/alignmentalgorithm executed by the base station 105-a and/or the UE 115-a, othertypes of directional link establishment techniques, or any combinationthereof. As part of establishing a directional link, the base station105-a and the UE 115-a may execute a handshake procedure. In someexamples, the establishment of a directional link may be based at leastin part on a relative location of the UE 115-a to the base station105-a.

In some examples, keepalive messages may be exchanged between the basestation 105-a and the UE 115-a. A keepalive message may refer to amessage sent by one device to another device to check that thecommunication link between the two devices is operating. The basestation 105-a may determine whether a keepalive message has beenreceived from the UE 115-a within a time threshold. If a keepalivemessage has not been received, the base station 105-a may not generate aCTS message 310-a and may not grant the requested communicationresources to the UE 115-a. The keepalive messages may be associated withthe directional communication links. A determination about the use ofmultiple timers may be based at least in part on whether keepalivemessages have been received. In some examples, if keepalive messageshave not been received, a RTS/CTS procedure (e.g., a procedure includingor based on using a RTS/CTS) using multiple timers may be used to ensurecommunication resources are preserved for other devices that haveestablished links with the base station.

At block 1010, the UE 115-a may determine whether to implement a RTS/CTSprocedure using multiple timers. As part of that determination, the UE115-a may identify data waiting to be sent to another entity (e.g., thebase station 105-a). In general, entities perform RTS/CTS proceduresafter determining that the entity needs to transmit data to anotherentity. The identified data may be generated by the UE 115-a. Thedetermination of whether to implement a RTS/CTS procedure using multipletimers may include measuring channel condition(s) associated with thedirectional communication link, determining whether a radio link failure(RLF) associated with the directional communication link has occurred,determining a duration of the data to be sent (e.g., duration 625), orany combinations thereof

At block 1015, the UE 115-a may measure at least one channel conditionassociated with the directional communication links already establishedbetween the UE 115-a and the base station 105-a (e.g., directionalcommunication link 205). The channel conditions that the UE 115-a maymeasure may include received signal strength, calibration error betweenelements of a phase array antenna, misalignment of a directionalcommunication link, lack of reciprocity between downlink directionalcommunication links and uplink directional communication links, networktraffic, network congestion, signal-to-noise ratio,signal-to-interference-to-noise ratio, reference signal strengthindicator (RSSI), reference signal received power (RSRP), referencesignal received quality (RSRQ), other types of channel conditions, orany combinations thereof.

Based at least in part on whether some channel conditions exist, the UE115-a may determine whether to initiate a RTS/CTS procedure thatincludes multiple timers. For example, if the measured channelconditions indicate there is heavy network traffic, the UE 115-a mayinitiate a RTS/CTS procedure that uses multiple timers. In addition, theUE 115-a may additionally or alternatively use the measured channelconditions to determine whether a RTS/CTS procedure is needed at all.For example, if the signal strength of an established directionalcommunication link is below a threshold, the UE 115-a may determine thatit should modify parameters of the communication link (e.g., directionor width). As part of modifying the communication link, the UE 115-a mayperform a RTS/CTS procedure to determine whether the UE 115-a mayrequest modifications to the established directional communication link.Other channel conditions may also be used to trigger a RTS/CTS procedureusing multiple timers.

At block 1020, the UE 115-a may determine that the establisheddirectional communication link has hit RLF. Upon determining that adirectional communication link 205 has experienced an RLF event, the UE115-a may begin using a dedicated set communication resources tore-establish the directional communication link 205. The dedicated setof communication resources may be different than the communicationresources used by the directional communication link 205. In addition,the dedicated set of communication resources may use the RTS/CTSprocedure to avoid communication collisions. In some examples, thededicated set of communication resources are implemented using adifferent RAT than what is used to implement the communication resourcesof the directional communication link 205. In some examples, identifyingthat an RLF event occurred may additionally or alternatively cause theUE 115-a to determine that multiple timers should be used in the RTS/CTSprocedure.

At block 1025, the UE 115-a may identify a duration of the data 415-awaiting to be transmitted by the UE 115-a. The duration of the data415-a waiting to be transmitted may be compared to a duration threshold.If the duration of the data 415-a satisfies the threshold, the UE 115-amay determine that the RTS/CTS procedure should include at least twotimers. In some examples, the UE 115-a may identify a size of the data415-a waiting to be transmitted by the UE 115-a. The size of the datamay be an actual size of the data, an expected size of the data, acalculated size, or any combinations thereof. In some examples, the sizeof the data may be expressed in bits, bytes, a duration of time totransmit, a number of frames, sub-frames, or slots, or any combinationsthereof.

The effects of unused communication resources due to over-lengthy timersmay be made more pronounced by larger data transmission. For example, ifthe duration of the data 415-a is short, not many resources may be lostusing a legacy NAV timer. However, if the duration of the data 415-a islong, a large amount of communication resources may go unused if the UE115-a does not receive permission use the requested resources. As such,the UE 115-a may determine how many timers to use based at least in parton the duration of the data 415-a waiting to be transmitted. In someexamples, if the duration of the data 415-a does not satisfy theduration threshold, one timer may be used in the RTS/CTS procedure. Inother examples, there may be multiple thresholds and the number oftimers used in the RTS/CTS procedure may be based at least in part onthe which thresholds are satisfied. For example, if a first threshold issatisfied but not a second threshold, the UE 115-a may determine thatthe RTS/CTS procedure should include two timers. If the first and secondthresholds are satisfied but not a third threshold, the UE 115-a maydetermine that the RTS/CTS procedure should include three timers, etc.In some examples, if the first threshold is not satisfied, the UE 115-amay determine that the RTS/CTS procedure should include one timer. Thedurations included in the timer data may be based at least in part onthe number of timers used in the RTS/CTS procedure. For example, thedurations used in a two timer RTS/CTS procedure may be different than aduration used in a single timer RTS/CTS procedure, and the durationsused in a three timer RTS/CTS procedure may be different than thedurations used in the two timer RTS/CTS procedure, etc.

At block 1030, the UE 115-a may determine new communication resources touse to execute a RTS/CTS procedure. The UE 115-a may communicate via anestablished directional communication link using a first set ofcommunication resources. If the established directional communicationlink is terminated prematurely for any reason, the UE 115-a may need toidentify a second set of communication resources to use to communicatewith the base station 105-a. The second set of communication resourcesmay be different than the first set of communication resources. Thesecond set of communication resources may use a different RAT than thefirst set of communication resources. For example, the directionalcommunication links may use a cellular RAT and the RTS/CTS procedure mayuse a Wi-Fi RAT.

At block 1035, the UE 115-a may determine timer data associated withmultiple timers to be used in a RTS/CTS procedure. Timer data may bedetermined for any number of timers determined to be part of themultiple timer RTS/CTS procedure. Block 1035 may be an example of blocks805, 820 described with reference to FIG. 8.

Communications group 1040 may represent any RTS/CTS procedure describedin this disclosure. The transmissions of the RTS message 305-a, the CTSmessage 310-a, and the data message 315-a are shown for illustrativepurposes only. Other transmissions, determinations, procedures,operations, and protocols may be included in the communications group1040.

FIG. 11 illustrates an example of a packet structure 1100 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. The packetstructure 1100 illustrates another example of how a RTS/CTS procedureusing multiple timers may be implemented. The packet structure 1100includes a RTS message 305-b, a CTS message 310-b, a second RTS message1105, and a data message 315-b. A difference between the packetstructure 1100 and the packet structure 700 described with reference toFIG. 7 may be that the second timer data 710-a may be included in thesecond RTS message 1105. The CTS message 310-b may contain a third timerdata (not shown) determined by the base station 105-b that instructsother UEs receiving the CTS message 310-b to refrain from transmittinguntil the expected end of the transmission of the data message 315-b.The expected end of the data message 315-b transmission is determined bythe base station 105-b based on the amount of data, the current uplinktransmission rate, etc., as conveyed in the other data 410-b field inRTS message 305-b from the UE 115-a.

The second RTS message 1105 may be transmitted based at least in part onreceiving the CTS message 310-b from the base station 105-b. The secondRTS message 1105 may be an example of the RTS messages 305 describedwith reference to FIGS. 3-10. The data message 315-b may be transmittedprior to receiving a second CTS message in response to the second RTSmessage 1105. The duration of the first timer data 705-a may be based atleast in part on an expected arrival time of the second RTS message1105. In some examples, the first timer data 705-a may include theduration 675 with or without an error margin 680.

The second RTS message 1105 may be a modified version of the other RTSmessages 305 described herein. The second RTS message 1105 may bemodified to indicate that no CTS message is required in response. Thesecond RTS message 1105 may be modified to cooperate with the datamessage 315-b during transmission. In this manner, the second RTSmessage 1105 and the data message 315-b may be a continuous transmissionwithout transmission gap.

The RTS message 305-b may be an example of the RTS message 305 describedwith reference to FIGS. 3-10. The CTS message 310-b may be an example ofthe CTS message 310 described with reference to FIGS. 3-10. The datamessage 315-b may be an example of the data message 315 described withreference to FIGS. 3-10. The other data 410-b may be an example of otherdata 410 described with reference to FIG. 4. The data 415-b may be anexample of data 415 described with reference to FIG. 4. The first timerdata 705-a may be an example of the first timer data 705 described withreference to FIGS. 7-10. The second timer data 710-a may be an exampleof the second timer data 710 described with reference to FIGS. 7-10.

FIG. 12 illustrates an example of a communication scheme 1200 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 1200 is associated with the packet structure 1100described with reference to FIG. 11. Many of the same features ofcommunication scheme 1200 have been described in connection withcommunication schemes 800, 900, 1000 found in FIGS. 8-10. As such,transmission, operations, and features having similar names and similarnumbers are not described in detail here.

After receiving the CTS message 310-b, at block 1220, the UE 115-a maydetermine the second timer data and generate a second RTS message 1105.The second RTS message 1105 may be transmitted to the base station 105-aand the UE 115-b. Block 1220 may be an example of block 820 describedwith reference to FIG. 8.

Upon receiving the second RTS message 1105, at block 1225, the UE 115-bmay set a second timer based on a duration include in the second timerdata 710-a. Block 1225 may be an example of block 825 described withreference to FIG. 8. The data message 315-b may be transmitted by the UE115-a to the base station 105-a.

FIG. 13 illustrates an example of a packet structure 1300 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. The packetstructure 1300 illustrates another example of how a RTS/CTS procedureusing multiple timers may be implemented. The packet structure 1300includes a RTS message 305-c, a CTS message 310-c, and a data message315-c.

The packet structure 1300 may rely on a predetermined duration stored onthe UE 115-b to initiate the first timer 505. As such, the RTS message305-c may include second timer data 710-b rather than first timer data705.

The RTS message 305-c may be an example of the RTS message 305 describedwith reference to FIGS. 3-10. The CTS message 310-c may be an example ofthe CTS message 310 described with reference to FIGS. 3-10. The datamessage 315-c may be an example of the data message 315 described withreference to FIGS. 3-10. The other data 410-c may be an example of otherdata 410 described with reference to FIG. 4. The data 415-c may be anexample of data 415 described with reference to FIG. 4. The second timerdata 710-b may be an example of the second timer data 710 described withreference to FIGS. 7-10. The CTS message 310-c may contain a third timerdata determined by the base station 105-b that instructs other UEsreceiving the CTS message 310-c to refrain from transmitting until theexpected end of the transmission of the data message 315-c. The expectedend of the data message 315-c transmission is determined by the basestation 105-b based on the amount of data, the current uplinktransmission rate, etc., as conveyed in the other data 410-c field inRTS message 305-c from the UE 115-a.

FIG. 14 illustrates an example of a communication scheme 1400 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 1400 is associated with the packet structure 1300described with reference to FIG. 13. Many of the same features ofcommunication scheme 1400 have been described in connection withcommunication schemes 800, 900, 1000 found in FIGS. 8-10. As such,transmission, operations, and features having similar names and similarnumbers are not described in detail here.

Upon receiving the RTS message 305-c that includes second timer data710-b, at block 1415, the UE 115-b may identify a predeterminedduration. The predetermined duration may be stored in a memory of the UE115-b. Because the durations and lengths of the RTS messages 305 and theCTS messages 310 is relatively fixed, it may not be needed to indicatethe duration associated with the first timer 505 in RTS messages 305. Assuch, the RTS message 305-c may include the second timer data 710-bhaving a duration related to a duration of the data 415-c in the datamessage 315-c.

At block 1420, the UE 115-b may set the first timer 505 based at leastin part on the predetermined duration and receiving the RTS message305-c having the second timer data 710-b. In some examples, the RTSmessage 305-c may include an indication that the its timer data issecond timer data 710-b and not some other timer data (e.g., a legacyNAV timer or first timer data 705).

FIG. 15 illustrates an example of a packet structure 1500 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. The packetstructure 1500 illustrates another example of how a RTS/CTS procedureusing multiple timers may be implemented. The packet structure 1500includes a RTS message 305-d, a CTS message 310-d, and a data message315-d.

The packet structure 1500 uses a RTS message 305-d that includes boththe first timer data 705-b and the second timer data 710-c. As such, theRTS message 305-d may be modified to include both timer data and may bemodified to indicate that the RTS message 305-d includes data formultiple timers.

The RTS message 305-d may be an example of the RTS message 305 describedwith reference to FIGS. 3-10. The CTS message 310-d may be an example ofthe CTS message 310 described with reference to FIGS. 3-10. The datamessage 315-d may be an example of the data message 315 described withreference to FIGS. 3-10. The other data 410-d may be an example of otherdata 410 described with reference to FIG. 4. The data 415-d may be anexample of data 415 described with reference to FIG. 4. The first timerdata 705-b may be an example of the first timer data 705 described withreference to FIGS. 7-10. The second timer data 710-c may be an exampleof the second timer data 710 described with reference to FIGS. 7-10. TheCTS message 310-d may contain a third timer data determined by the basestation 105-b that instructs other UEs receiving the CTS message 310-dto refrain from transmitting until the expected end of the transmissionof the data message 315-d. The expected end of the data message 315-dtransmission is determined by the base station 105-b based on the amountof data, the current uplink transmission rate, etc., as conveyed in theother data 410-d field in RTS message 305-d from the UE 115-a.

FIG. 16 illustrates an example of a communication scheme 1600 used formultiple timers for request to send and clear to send communications inaccordance with various aspects of the present disclosure. Thecommunication scheme 1600 is associated with the packet structure 1500described with reference to FIG. 15. Many of the same features ofcommunication scheme 1600 have been described in connection withcommunication schemes 800, 900, 1000 found in FIGS. 8-10. As such,transmission, operations, and features having similar names and similarnumbers are not described in detail here.

At block 1615, the UE 115-b may set a first timer 505 based at least inpart on first timer data 705-b included in the RTS message 305-d andreception of the RTS message 305-d. In addition, at block 1620, the UE115-b may set a second timer 510 based at least in part on second timerdata 710-c included in the RTS message 305-d and reception of the CTSmessage 310-d prior to the expiration of the first timer 505.

FIG. 17 shows a block diagram 1700 of a wireless device 1705 thatsupports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. Wireless device 1705 may be an example of aspects of a UE115 as described with reference to FIG. 1. Wireless device 1705 mayinclude receiver 1710, UE communications manager 1715, and transmitter1720. Wireless device 1705 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 1710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to multipletimers for request to send and clear to send communications).Information may be passed on to other components of the device. Thereceiver 1710 may be an example of aspects of the transceiver 2035described with reference to FIG. 20.

UE communications manager 1715 may be an example of aspects of the UEcommunications manager 2015 described with reference to FIG. 20.

UE communications manager 1715 may determine a first timer based on aduration for transmitting a first RTS message and a duration forreceiving a CTS message, transmit the first RTS message associated withthe first timer, receive the CTS message before an expiration of thefirst timer based on the first RTS message, and transmit, in response toreceiving the CTS message, a data message having a second timerdifferent from the first timer, the data message associated with a datatransmission opportunity for the UE. In some examples, the second timercomprises a NAV timer.

The UE communications manager 1715 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the UE communicationsmanager 1715 may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), an field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure. The UE communications manager 1715and/or at least some of its various sub-components may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical devices. In some examples, UE communicationsmanager 1715 and/or at least some of its various sub-components may be aseparate and distinct component in accordance with various aspects ofthe present disclosure. In other examples, UE communications manager1715 and/or at least some of its various sub-components may be combinedwith one or more other hardware components, including but not limited toa receiver, a transmitter, or a transceiver in accordance with variousaspects of the present disclosure.

Transmitter 1720 may transmit signals generated by other components ofthe device. In some examples, the transmitter 1720 may be collocatedwith a receiver 1710 in a transceiver module. For example, thetransmitter 1720 may be an example of aspects of the transceiver 2035described with reference to FIG. 20. The transmitter 1720 may include asingle antenna, or it may include a set of antennas.

FIG. 18 shows a block diagram 1800 of a wireless device 1805 thatsupports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. Wireless device 1805 may be an example of aspects of awireless device 1705 or a UE 115 as described with reference to FIGS. 1and 17. Wireless device 1805 may include receiver 1810, UEcommunications manager 1815, and transmitter 1820. Wireless device 1805may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

Receiver 1810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to multipletimers for request to send and clear to send communications).Information may be passed on to other components of the device. Thereceiver 1810 may be an example of aspects of the transceiver 2035described with reference to FIG. 20.

UE communications manager 1815 may be an example of aspects of the UEcommunications manager 2015 described with reference to FIG. 20.

UE communications manager 1815 may also include timer manager 1825,message manager 1830, and data manager 1835.

Timer manager 1825 may determine a first timer based on a duration fortransmitting a first RTS message and a duration for receiving a CTSmessage, identify a duration of the data transmission opportunity forthe UE, determine the second timer based on the duration of the datatransmission opportunity, compare a duration of the data message to athreshold, and determine the second timer based on the duration of thedata message exceeding the threshold. In some cases, the second timerhas a longer duration than the first timer.

Message manager 1830 may transmit the first RTS message associated withthe first timer and receive the CTS message before an expiration of thefirst timer based on the first RTS message. In some cases, transmittingthe first RTS message may additionally or alternatively includetransmitting the first RTS message using a second set of communicationresources different than the first set of communication resources.

Data manager 1835 may transmit, in response to receiving the CTSmessage, a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor the UE, set the second timer based on the size being greater thanthe threshold, determine a size of data associated with the datamessage, if the size is less than a threshold then: determine the firsttimer based on the duration for transmitting the first RTS message, theduration for receiving the CTS message, and the duration fortransmitting the data message, transmit the first RTS message associatedwith the first timer, transmit, in response to receiving the CTSmessage, the data message; and, if the size is greater than thethreshold then: determine the first timer based at least in part on theduration for transmitting the first RTS message and the duration forreceiving the CTS message, transmit the first RTS message associatedwith the first timer, receive the CTS message before the expiration ofthe first timer, transmit, in response to receiving the CTS message, thedata message having the second timer different from the first timer,identify a size of data associated with the data message, compare thesize to a threshold, where the first timer, or the second timer, or bothare based on the comparison, set the second timer based on the sizebeing less than the threshold, and determine the first timer based onthe duration for transmitting the first RTS message and the duration forreceiving the CTS message. In some cases, the data message includes asecond RTS message.

Transmitter 1820 may transmit signals generated by other components ofthe device. In some examples, the transmitter 1820 may be collocatedwith a receiver 1810 in a transceiver module. For example, thetransmitter 1820 may be an example of aspects of the transceiver 2035described with reference to FIG. 20. The transmitter 1820 may include asingle antenna, or it may include a set of antennas.

The UE communications manager 1815 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the UE communicationsmanager 1815 and/or at least some of its various sub-components may beexecuted by a general-purpose processor, a DSP, an ASIC, an FPGA orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described in the present disclosure. The UEcommunications manager 1815 and/or at least some of its varioussub-components may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, UE communications manager 1815 and/or at least some of itsvarious sub-components may be a separate and distinct component inaccordance with various aspects of the present disclosure. In otherexamples, UE communications manager 1815 may be combined with one ormore other hardware components, including but not limited to a receiver1810, a transmitter 1820, a transceiver, a timer manager 1825, a messagemanager 1830, or a data manager 1835 in accordance with various aspectsof the present disclosure.

FIG. 19 shows a block diagram 1900 of a UE communications manager 1915that supports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. The UE communications manager 1915 may be an example ofaspects of a UE communications manager 1715, a UE communications manager1815, or a UE communications manager 2015 described with reference toFIGS. 17, 18, and 20. The UE communications manager 1915 may includetimer manager 1920, message manager 1925, data manager 1930, linkmanager 1935, and channel condition manager 1940. Each of these modulesmay communicate, directly or indirectly, with one another (e.g., via oneor more buses).

Timer manager 1920 may determine a first timer based on a duration fortransmitting a first RTS message and a duration for receiving a CTSmessage, identify a duration of the data transmission opportunity forthe UE, determine the second timer based on the duration of the datatransmission opportunity, compare a duration of the data message to athreshold, and determine the second timer based on the duration of thedata message exceeding the threshold. In some cases, the second timerhas a longer duration than the first timer.

Message manager 1925 may transmit the first RTS message associated withthe first timer and receive the CTS message before an expiration of thefirst timer based on the first RTS message. In some cases, transmittingthe first RTS message further includes: transmitting the first RTSmessage using a second set of communication resources different than thefirst set of communication resources.

Data manager 1930 may transmit, in response to receiving the CTSmessage, a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor the UE, set the second timer based on the size being greater thanthe threshold, determine a size of data associated with the datamessage, if the size is less than a threshold then: determine the firsttimer based on the duration for transmitting the first RTS message, theduration for receiving the CTS message, and the duration fortransmitting the data message, transmit the first RTS message associatedwith the first timer, transmit, in response to receiving the CTSmessage, the data message; and, if the size is greater than thethreshold then: determine the first timer based at least in part on theduration for transmitting the first RTS message and the duration forreceiving the CTS message, transmit the first RTS message associatedwith the first timer, receive the CTS message before the expiration ofthe first timer, transmit, in response to receiving the CTS message, thedata message having the second timer different from the first timer,identify a size of data associated with the data message, compare thesize to a threshold, where the first timer, or the second timer, or bothare based on the comparison, set the second timer based on the sizebeing less than the threshold, and determine the first timer based onthe duration for transmitting the first RTS message and the duration forreceiving the CTS message. In some cases, the data message includes asecond RTS message.

Link manager 1935 may establish a directional communication link with abase station, the directional communication link using a first set ofcommunication resources and identify that a radio link failure eventassociated with the directional communication link has occurred, wheretransmitting the first RTS message is based on identifying that theradio link failure event occurred. In some cases, the first set ofcommunication resources include a RAT. In some cases, the second set ofcommunication resources include a second RAT different from the firstRAT. In some cases, the first RTS message, the CTS message, and the datamessage are transmitted using a cellular radio access technology.

Channel condition manager 1940 may measure a channel conditionassociated with the directional communication link, where transmittingthe first RTS message is based on the measured channel conditionassociated with the directional communication link.

The UE communications manager 1915 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the UE communicationsmanager 1915 and/or at least some of its various sub-components may beexecuted by a general-purpose processor, a DSP, an ASIC, an FPGA orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described in the present disclosure. The UEcommunications manager 1915 and/or at least some of its varioussub-components may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, UE communications manager 1915 and/or at least some of itsvarious sub-components may be a separate and distinct component inaccordance with various aspects of the present disclosure. In otherexamples, UE communications manager 1915 and/or at least some of itsvarious sub-components may be combined with one or more other hardwarecomponents, including but not limited to a receiver, a transmitter, atransceiver, a timer manager 1920, a message manager 1925, data manager1930, a link manager 1935, or a channel condition manager 1940 inaccordance with various aspects of the present disclosure.

FIG. 20 shows a diagram of a system 2000 including a device 2005 thatsupports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. Device 2005 may be an example of or include the componentsof wireless device 1705, wireless device 1805, or a UE 115 as describedabove, e.g., with reference to FIGS. 1, 17 and 18. Device 2005 mayinclude components for bi-directional voice and data communicationsincluding components for transmitting and receiving communications,including UE communications manager 2015, processor 2020, memory 2025,software 2030, transceiver 2035, antenna 2040, and I/O controller 2045.These components may be in electronic communication via one or morebusses (e.g., bus 2010). Device 2005 may communicate wirelessly with oneor more base stations 105.

Processor 2020 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, processor 2020may be configured to operate a memory array using a memory controller.In other cases, a memory controller may be integrated into processor2020. Processor 2020 may be configured to execute computer-readableinstructions stored in a memory to perform various functions (e.g.,functions or tasks supporting multiple timers for request to send andclear to send communications).

Memory 2025 may include random access memory (RAM) and read only memory(ROM). The memory 2025 may store computer-readable, computer-executablesoftware 2030 including instructions that, when executed, cause theprocessor to perform various functions described herein. In some cases,the memory 2025 may contain, among other things, a basic input/outputsystem (BIOS) which may control basic hardware and/or software operationsuch as the interaction with peripheral components or devices.

Software 2030 may include code to implement aspects of the presentdisclosure, including code to support multiple timers for request tosend and clear to send communications. Software 2030 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 2030 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 2035 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 2035 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 2035 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 2040.However, in some cases the device may have more than one antenna 2040,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

I/O controller 2045 may manage input and output signals for device 2005.I/O controller 2045 may also manage peripherals not integrated intodevice 2005. In some cases, I/O controller 2045 may represent a physicalconnection or port to an external peripheral. In some cases, I/Ocontroller 2045 may utilize an operating system such as iOS®, ANDROID®,MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operatingsystem.

FIG. 21 shows a block diagram 2100 of a wireless device 2105 thatsupports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. Wireless device 2105 may be an example of aspects of a basestation 105 as described with reference to FIG. 1. Wireless device 2105may include receiver 2110, base station communications manager 2115, andtransmitter 2120. Wireless device 2105 may also include a processor.Each of these components may be in communication with one another (e.g.,via one or more buses).

Receiver 2110 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to multipletimers for request to send and clear to send communications).Information may be passed on to other components of the device. Thereceiver 2110 may be an example of aspects of the transceiver 2435described with reference to FIG. 24.

Base station communications manager 2115 may be an example of aspects ofthe base station communications manager 2450 described with reference toFIG. 24.

Base station communications manager 2115 may receive a RTS messagehaving a first timer based on a duration for receiving the RTS messageand a duration for transmitting a CTS message, transmit the CTS messagebefore an expiration of the first timer based on the RTS message, andreceive a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor a UE. In some examples, the second timer comprises a NAV timer.

The base station communications manager 2115 and/or at least some of itsvarious sub-components may be implemented in hardware, software executedby a processor, firmware, or any combination thereof If implemented insoftware executed by a processor, the functions of the base stationcommunications manager 2115 and/or at least some of its varioussub-components may be executed by a general-purpose processor, a DSP, anASIC, an FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure. The base station communications manager 2115 and/or at leastsome of its various sub-components may be physically located at variouspositions, including being distributed such that portions of functionsare implemented at different physical locations by one or more physicaldevices. In some examples, base station communications manager 2115and/or at least some of its various sub-components may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station communications manager 2115and/or at least some of its various sub-components may be combined withone or more other hardware components, including but not limited to areceiver, a transmitter, or a transceiver in accordance with variousaspects of the present disclosure.

Transmitter 2120 may transmit signals generated by other components ofthe device. In some examples, the transmitter 2120 may be collocatedwith a receiver 2110 in a transceiver module. For example, thetransmitter 2120 may be an example of aspects of the transceiver 2435described with reference to FIG. 24. The transmitter 2120 may include asingle antenna, or it may include a set of antennas.

FIG. 22 shows a block diagram 2200 of a wireless device 2205 thatsupports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. Wireless device 2205 may be an example of aspects of awireless device 2105 or a base station 105 as described with referenceto FIGS. 1 and 21. Wireless device 2205 may include receiver 2210, basestation communications manager 2215, and transmitter 2220. Wirelessdevice 2205 may also include a processor. Each of these components maybe in communication with one another (e.g., via one or more buses).

Receiver 2210 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to multipletimers for request to send and clear to send communications).Information may be passed on to other components of the device. Thereceiver 2210 may be an example of aspects of the transceiver 2435described with reference to FIG. 24.

Base station communications manager 2215 may be an example of aspects ofthe base station communications manager 2450 described with reference toFIG. 24.

Base station communications manager 2215 may also include messagemanager 2225 and data manager 2230.

Message manager 2225 may receive a RTS message having a first timerbased on a duration for receiving the RTS message and a duration fortransmitting a CTS message and transmit the CTS message before anexpiration of the first timer based on the RTS message.

Data manager 2230 may receive a data message having a second timerdifferent from the first timer, the data message associated with a datatransmission opportunity for a UE and receive the data message duringthe second timer. In some cases, at least a part of the data message isreceived from the UE, in response to the second RTS message, beforetransmitting a second CTS message. In some cases, the data messageincludes information indicating a duration of the second timer. In somecases, the data message includes a second RTS message.

Transmitter 2220 may transmit signals generated by other components ofthe device. In some examples, the transmitter 2220 may be collocatedwith a receiver 2210 in a transceiver module. For example, thetransmitter 2220 may be an example of aspects of the transceiver 2435described with reference to FIG. 24. The transmitter 2220 may include asingle antenna, or it may include a set of antennas.

The base station communications manager 2215 and/or at least some of itsvarious sub-components may be implemented in hardware, software executedby a processor, firmware, or any combination thereof If implemented insoftware executed by a processor, the functions of the base stationcommunications manager 2215 and/or at least some of its varioussub-components may be executed by a general-purpose processor, a DSP, anASIC, an FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure. The base station communications manager 2215 and/or at leastsome of its various sub-components may be physically located at variouspositions, including being distributed such that portions of functionsare implemented at different physical locations by one or more physicaldevices. In some examples, base station communications manager 2215and/or at least some of its various sub-components may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station communications manager 2215and/or at least some of its various sub-components may be combined withone or more other hardware components, including but not limited to areceiver 2210, a transmitter 2220, a transceiver, a message manager2225, or a data manager 2230 in accordance with various aspects of thepresent disclosure.

FIG. 23 shows a block diagram 2300 of a base station communicationsmanager 2315 that supports multiple timers for request to send and clearto send communications in accordance with various aspects of the presentdisclosure. The base station communications manager 2315 may be anexample of aspects of a base station communications manager 2450described with reference to FIGS. 21, 22, and 24. The base stationcommunications manager 2315 may include message manager 2320, datamanager 2325, idle manager 2330, timer manager 2335, and link manager2340. Each of these modules may communicate, directly or indirectly,with one another (e.g., via one or more buses).

Message manager 2320 may receive a RTS message having a first timerbased on a duration for receiving the RTS message and a duration fortransmitting a CTS message and transmit the CTS message before anexpiration of the first timer based on the RTS message.

Data manager 2325 may receive a data message having a second timerdifferent from the first timer, the data message associated with a datatransmission opportunity for a UE and receive the data message duringthe second timer. In some cases, at least a part of the data message isreceived from the UE, in response to the second RTS message, beforetransmitting a second CTS message. In some cases, the data messageincludes information indicating a duration of the second timer. In somecases, the data message includes a second RTS message.

Idle manager 2330 may remain idle during the indicated duration of thesecond timer in response to receiving the data message.

Timer manager 2335 may be configured to manage timer data. In somecases, the second timer is longer than the first timer.

Link manager 2340 may establish a directional communication link withthe UE, the directional communication link using a first set ofcommunication resources, where the RTS message is received using asecond set of communication resources different than the first set ofcommunication resources and determine whether a keepalive message hasbeen received from the UE, where transmitting the CTS message is basedon the keepalive message.

The base station communications manager 2315 and/or at least some of itsvarious sub-components may be implemented in hardware, software executedby a processor, firmware, or any combination thereof If implemented insoftware executed by a processor, the functions of the base stationcommunications manager 2315 and/or at least some of its varioussub-components may be executed by a general-purpose processor, a DSP, anASIC, an FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure. The base station communications manager 2315 and/or at leastsome of its various sub-components may be physically located at variouspositions, including being distributed such that portions of functionsare implemented at different physical locations by one or more physicaldevices. In some examples, base station communications manager 2315and/or at least some of its various sub-components may be a separate anddistinct component in accordance with various aspects of the presentdisclosure. In other examples, base station communications manager 2315and/or at least some of its various sub-components may be combined withone or more other hardware components, including but not limited to areceiver, a transmitter, a transceiver, a message manager 2320, a datamanager 2325, an idle manager 2330, a timer manager 2335, or a linkmanager 2340 in accordance with various aspects of the presentdisclosure.

FIG. 24 shows a diagram of a system 2400 including a device 2405 thatsupports multiple timers for request to send and clear to sendcommunications in accordance with various aspects of the presentdisclosure. Device 2405 may be an example of or include the componentsof base station 105 as described above, e.g., with reference to FIG. 1.Device 2405 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including base station communications manager 2450,processor 2420, memory 2425, software 2430, transceiver 2435, antenna2440, network communications manager 2445, and base stationcommunications manager 2450. These components may be in electroniccommunication via one or more busses (e.g., bus 2410). Device 2405 maycommunicate wirelessly with one or more UEs 115.

Processor 2420 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, processor 2420 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into processor 2420. Processor 2420 may be configured toexecute computer-readable instructions stored in a memory to performvarious functions (e.g., functions or tasks supporting multiple timersfor request to send and clear to send communications).

Memory 2425 may include RAM and ROM. The memory 2425 may storecomputer-readable, computer-executable software 2430 includinginstructions that, when executed, cause the processor to perform variousfunctions described herein. In some cases, the memory 2425 may contain,among other things, a BIOS which may control basic hardware and/orsoftware operation such as the interaction with peripheral components ordevices.

Software 2430 may include code to implement aspects of the presentdisclosure, including code to support multiple timers for request tosend and clear to send communications. Software 2430 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 2430 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 2435 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 2435 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 2435 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 2440.However, in some cases the device may have more than one antenna 2440,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

Network communications manager 2445 may manage communications with thecore network (e.g., via one or more wired backhaul links). For example,the network communications manager 2445 may manage the transfer of datacommunications for client devices, such as one or more UEs 115.

Base station communications manager 2450 and/or at least some of itsvarious sub-components may manage communications with other base station105, and may include a controller or scheduler for controllingcommunications with UEs 115 in cooperation with other base stations 105.For example, the base station communications manager 2450 and/or atleast some of its various sub-components may coordinate scheduling fortransmissions to UEs 115 for various interference mitigation techniquessuch as beamforming or joint transmission. In some examples, basestation communications manager 2450 and/or at least some of its varioussub-components may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

FIG. 25 shows a flowchart illustrating a method 2500 for multiple timersfor request to send and clear to send communications in accordance withvarious aspects of the present disclosure. The operations of method 2500may be implemented by a UE 115 or its components as described herein.For example, the operations of method 2500 may be performed by a UEcommunications manager as described with reference to FIGS. 17 through20. In some examples, a UE 115 may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the UE 115 may perform aspects thefunctions described below using special-purpose hardware.

At block 2505 the UE 115 may determine a first timer based at least inpart on a duration for transmitting a first RTS message and a durationfor receiving a CTS message. The operations of block 2505 may beperformed according to the methods described with reference to FIGS. 1through 16. In some examples, aspects of the operations of block 2505may be performed by a timer manager as described with reference to FIGS.17 through 20.

At block 2510 the UE 115 may transmit the first RTS message associatedwith the first timer. The operations of block 2510 may be performedaccording to the methods described with reference to FIGS. 1 through 16.In some examples, aspects of the operations of block 2510 may beperformed by a message manager as described with reference to FIGS. 17through 20.

At block 2515 the UE 115 may receive the CTS message before anexpiration of the first timer based at least in part on the first RTSmessage. The operations of block 2515 may be performed according to themethods described with reference to FIGS. 1 through 16. In someexamples, aspects of the operations of block 2515 may be performed by amessage manager as described with reference to FIGS. 17 through 20.

At block 2520 the UE 115 may transmit, in response to receiving the CTSmessage, a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor the UE. The operations of block 2520 may be performed according tothe methods described with reference to FIGS. 1 through 16. In someexamples, aspects of the operations of block 2520 may be performed by adata manager as described with reference to FIGS. 17 through 20.

FIG. 26 shows a flowchart illustrating a method 2600 for multiple timersfor request to send and clear to send communications in accordance withvarious aspects of the present disclosure. The operations of method 2600may be implemented by a UE 115 or its components as described herein.For example, the operations of method 2600 may be performed by a UEcommunications manager as described with reference to FIGS. 17 through20. In some examples, a UE 115 may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the UE 115 may perform aspects thefunctions described below using special-purpose hardware.

At block 2605 the UE 115 may determine a first timer based at least inpart on a duration for transmitting a first RTS message and a durationfor receiving a CTS message. The operations of block 2605 may beperformed according to the methods described with reference to FIGS. 1through 16. In some examples, aspects of the operations of block 2605may be performed by a timer manager as described with reference to FIGS.17 through 20.

At block 2610 the UE 115 may transmit the first RTS message associatedwith the first timer. The operations of block 2610 may be performedaccording to the methods described with reference to FIGS. 1 through 16.In some examples, aspects of the operations of block 2610 may beperformed by a message manager as described with reference to FIGS. 17through 20.

At block 2615 the UE 115 may receive the CTS message before anexpiration of the first timer based at least in part on the first RTSmessage. The operations of block 2615 may be performed according to themethods described with reference to FIGS. 1 through 16. In someexamples, aspects of the operations of block 2615 may be performed by amessage manager as described with reference to FIGS. 17 through 20.

At block 2620 the UE 115 may identify a duration of the datatransmission opportunity for the UE. The operations of block 2620 may beperformed according to the methods described with reference to FIGS. 1through 16. In some examples, aspects of the operations of block 2620may be performed by a timer manager as described with reference to FIGS.17 through 20.

At block 2625 the UE 115 may determine the second timer based at leastin part on the duration of the data transmission opportunity. Theoperations of block 2625 may be performed according to the methodsdescribed with reference to FIGS. 1 through 16. In some examples,aspects of the operations of block 2625 may be performed by a timermanager as described with reference to FIGS. 17 through 20.

At block 2630 the UE 115 may transmit, in response to receiving the CTSmessage, a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor the UE. The operations of block 2630 may be performed according tothe methods described with reference to FIGS. 1 through 16. In someexamples, aspects of the operations of block 2630 may be performed by adata manager as described with reference to FIGS. 17 through 20.

FIG. 27 shows a flowchart illustrating a method 2700 for multiple timersfor request to send and clear to send communications in accordance withvarious aspects of the present disclosure. The operations of method 2700may be implemented by a base station 105 or its components as describedherein. For example, the operations of method 2700 may be performed by abase station communications manager as described with reference to FIGS.21 through 24. In some examples, a base station 105 may execute a set ofcodes to control the functional elements of the device to perform thefunctions described below. Additionally or alternatively, the basestation 105 may perform aspects the functions described below usingspecial-purpose hardware.

At block 2705 the base station 105 may receive a RTS message having afirst timer based at least in part on a duration for receiving the RTSmessage and a duration for transmitting a CTS message. The operations ofblock 2705 may be performed according to the methods described withreference to FIGS. 1 through 16. In some examples, aspects of theoperations of block 2705 may be performed by a message manager asdescribed with reference to FIGS. 21 through 24.

At block 2710 the base station 105 may transmit the CTS message beforean expiration of the first timer based at least in part on the RTSmessage. The operations of block 2710 may be performed according to themethods described with reference to FIGS. 1 through 16. In someexamples, aspects of the operations of block 2710 may be performed by amessage manager as described with reference to FIGS. 21 through 24.

At block 2715 the base station 105 may receive a data message having asecond timer different from the first timer, the data message associatedwith a data transmission opportunity for a UE. The operations of block2715 may be performed according to the methods described with referenceto FIGS. 1 through 16. In some examples, aspects of the operations ofblock 2715 may be performed by a data manager as described withreference to FIGS. 21 through 24.

FIG. 28 shows a flowchart illustrating a method 2800 for multiple timersfor request to send and clear to send communications in accordance withvarious aspects of the present disclosure. The operations of method 2800may be implemented by a base station 105 or its components as describedherein. For example, the operations of method 2800 may be performed by abase station communications manager as described with reference to FIGS.21 through 24. In some examples, a base station 105 may execute a set ofcodes to control the functional elements of the device to perform thefunctions described below. Additionally or alternatively, the basestation 105 may perform aspects the functions described below usingspecial-purpose hardware.

At block 2805 the base station 105 may establish a directionalcommunication link with the UE, the directional communication link usinga first set of communication resources, wherein the RTS message isreceived using a second set of communication resources different thanthe first set of communication resources. The operations of block 2805may be performed according to the methods described with reference toFIGS. 1 through 16. In some examples, aspects of the operations of block2805 may be performed by a link manager as described with reference toFIGS. 21 through 24.

At block 2810 the base station 105 may receive a RTS message having afirst timer based at least in part on a duration for receiving the RTSmessage and a duration for transmitting a CTS message. The operations ofblock 2810 may be performed according to the methods described withreference to FIGS. 1 through 16. In some examples, aspects of theoperations of block 2810 may be performed by a message manager asdescribed with reference to FIGS. 21 through 24.

At block 2815 the base station 105 may transmit the CTS message beforean expiration of the first timer based at least in part on the RTSmessage. The operations of block 2815 may be performed according to themethods described with reference to FIGS. 1 through 16. In someexamples, aspects of the operations of block 2815 may be performed by amessage manager as described with reference to FIGS. 21 through 24.

At block 2820 the base station 105 may receive a data message having asecond timer different from the first timer, the data message associatedwith a data transmission opportunity for a UE. The operations of block2820 may be performed according to the methods described with referenceto FIGS. 1 through 16. In some examples, aspects of the operations ofblock 2820 may be performed by a data manager as described withreference to FIGS. 21 through 24.

It should be noted that the methods described above describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Furthermore, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, single carrierfrequency division multiple access (SC-FDMA), and other systems. Theterms “system” and “network” are often used interchangeably. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases may be commonly referred to asCDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications system (UMTS). 3GPP LTE and LTE-A are releases ofUniversal Mobile Telecommunications System (UMTS) that use E-UTRA. UTRA,E-UTRA, UMTS, LTE, LTE-A, and Global System for Mobile communications(GSM) are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies. While aspects an LTE system may be described forpurposes of example, and LTE terminology may be used in much of thedescription, the techniques described herein are applicable beyond LTEapplications.

In LTE/LTE-A networks, including such networks described herein, theterm evolved node B (eNB) may be generally used to describe the basestations. The wireless communications system or systems described hereinmay include a heterogeneous LTE/LTE-A network in which different typesof evolved node B (eNBs) provide coverage for various geographicalregions. For example, each eNB or base station may provide communicationcoverage for a macro cell, a small cell, or other types of cell. Theterm “cell” may be used to describe a base station, a carrier orcomponent carrier associated with a base station, or a coverage area(e.g., sector) of a carrier or base station, depending on context.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an accesspoint, a radio transceiver, a NodeB, eNodeB (eNB), Home NodeB, a HomeeNodeB, or some other suitable terminology. The geographic coverage areafor a base station may be divided into sectors making up only a portionof the coverage area. The wireless communications system or systemsdescribed herein may include base stations of different types (e.g.,macro or small cell base stations). The UEs described herein may be ableto communicate with various types of base stations and network equipmentincluding macro eNBs, small cell eNBs, relay base stations, and thelike. There may be overlapping geographic coverage areas for differenttechnologies.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed) frequencybands as macro cells. Small cells may include pico cells, femto cells,and micro cells according to various examples. A pico cell, for example,may cover a small geographic area and may allow unrestricted access byUEs with service subscriptions with the network provider. A femto cellmay also cover a small geographic area (e.g., a home) and may providerestricted access by UEs having an association with the femto cell(e.g., UEs in a closed subscriber group (CSG), UEs for users in thehome, and the like). An eNB for a macro cell may be referred to as amacro eNB. An eNB for a small cell may be referred to as a small celleNB, a pico eNB, a femto eNB, or a home eNB. An eNB may support one ormultiple (e.g., two, three, four, and the like) cells (e.g., componentcarriers). A UE may be able to communicate with various types of basestations and network equipment including macro eNBs, small cell eNBs,relay base stations, and the like.

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The downlink transmissions described herein may also be called forwardlink transmissions while the uplink transmissions may also be calledreverse link transmissions. Each communication link describedherein—including, for example, wireless communications system 100 and200 of FIGS. 1 and 2—may include one or more carriers, where eachcarrier may be a signal made up of multiple sub-carriers (e.g., waveformsignals of different frequencies).

The description set forth herein, in connection with the appendeddrawings, describes examples and does not represent all the examplesthat may be implemented or that are within the scope of the claims. Theterm “exemplary” used herein means “serving as an example, instance, orillustration,” and not “preferred” or “advantageous over otherexamples.” The detailed description includes specific details for thepurpose of providing an understanding of the described techniques. Thesetechniques, however, may be practiced without these specific details. Insome instances, well-known structures and devices are shown in blockdiagram form in order to avoid obscuring the concepts of the describedexamples.

In the appended figures, similar components or features may have thesame reference label. Additionally or alternatively, various componentsof the same type may be distinguished by following the reference labelby a dash and a second label that distinguishes among the similarcomponents. If just the first reference label is used in thespecification, the description is applicable to any one of the similarcomponents having the same first reference label irrespective of thesecond reference label.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchexample).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. As used herein, including in the claims,the term “and/or,” when used in a list of two or more items, means thatany one of the listed items can be employed by itself, or anycombination of two or more of the listed items can be employed. Forexample, if a composition is described as containing components A, B,and/or C, the composition can contain A alone; B alone; C alone; A and Bin combination; A and C in combination; B and C in combination; or A, B,and C in combination. Also, as used herein, including in the claims,“or” as used in a list of items (for example, a list of items prefacedby a phrase such as “at least one of” or “one or more of”) indicates aninclusive list such that, for example, a phrase referring to “at leastone of” a list of items refers to any combination of those items,including single members. As an example, “at least one of: A, B, or C”is intended to cover A, B, C, A-B, A-C, B-C, and A-B-C., as well as anycombination with multiples of the same element (e.g., A-A A-A-A, A-A-B,A-A-C, A-B-B, A-C-C, B-B, B-B-B, B-B-C, C-C, and C-C-C or any otherordering of A, B, and C).

As used herein, the phrase “based on” shall not be construed as areference to a closed set of conditions. For example, an exemplary stepthat is described as “based on condition A” may be based on both acondition A and a condition B without departing from the scope of thepresent disclosure. In other words, as used herein, the phrase “basedon” shall be construed in the same manner as the phrase “based at leastin part on.”

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media cancomprise RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

1. (canceled)
 2. A method for wireless communication by a device,comprising: determining a first timer based at least in part on aduration for transmitting a first request to send message and a durationfor receiving a clear to send message; transmitting the first request tosend message associated with the first timer; and transmitting a datamessage having a second timer different from the first timer, the datamessage associated with a data transmission opportunity for the device.3. The method of claim 2, further comprising: receiving the clear tosend message before an expiration of the first timer based at least inpart on the first request to send message.
 4. The method of claim 3,wherein transmitting the data message having the second timer is inresponse to receiving the clear to send message.
 5. The method of claim2, wherein the second timer comprises a network allocation vector timer.6. The method of claim 2, wherein the data message comprises a secondrequest to send message.
 7. The method of claim 2, wherein the secondtimer has a longer duration than the first timer.
 8. The method of claim2, further comprising: identifying a duration of the data transmissionopportunity for the device; and determining the second timer based atleast in part on the duration of the data transmission opportunity. 9.The method of claim 2, further comprising: establishing a directionalcommunication link with a second device, the directional communicationlink using a first set of communication resources.
 10. The method ofclaim 9, further comprising: measuring a channel condition associatedwith the directional communication link, wherein transmitting the firstrequest to send message is based at least in part on the channelcondition associated with the directional communication link.
 11. Themethod of claim 9, further comprising: identifying that a radio linkfailure event associated with the directional communication link hasoccurred, wherein transmitting the first request to send message isbased at least in part on identifying that the radio link failure eventoccurred.
 12. The method of claim 9, wherein transmitting the firstrequest to send message further comprises: transmitting the firstrequest to send message using a second set of communication resourcesdifferent than the first set of communication resources.
 13. The methodof claim 12, wherein: the first set of communication resources comprisea first radio access technology; and the second set of communicationresources comprise a second radio access technology different from thefirst radio access technology.
 14. The method of claim 2, wherein thefirst request to send message, the clear to send message, and the datamessage are transmitted using a cellular radio access technology. 15.The method of claim 2, further comprising: comparing a duration of thedata message to a threshold; and determining the second timer based atleast in part on the duration of the data message exceeding thethreshold.
 16. The method of claim 2, further comprising: determiningthat a size of data associated with the data message is less than athreshold; determining the first timer based at least in part on theduration for transmitting the first request to send message, theduration for receiving the clear to send message, and the duration fortransmitting the data message; transmitting the first request to sendmessage associated with the first timer; and transmitting, in responseto receiving the clear to send message, the data message.
 17. The methodof claim 2, further comprising: determining that a size of dataassociated with the data message is greater than a threshold;determining the first timer based at least in part on the duration fortransmitting the first request to send message and the duration forreceiving the clear to send message; transmitting the first request tosend message associated with the first timer; receiving the clear tosend message before an expiration of the first timer; and transmitting,in response to receiving the clear to send message, the data messagehaving the second timer different from the first timer.
 18. A method forwireless communication by a first device, comprising: receiving arequest to send message having a first timer based at least in part on aduration for receiving the request to send message and a duration fortransmitting a clear to send message; and receiving a data messagehaving a second timer different from the first timer, the data messageassociated with a data transmission opportunity for a second device. 19.The method of claim 18, further comprising: transmitting the clear tosend message before an expiration of the first timer based at least inpart on the request to send message.
 20. The method of claim 18, whereinthe second timer comprises a network allocation vector timer.
 21. Themethod of claim 18, further comprising: receiving the data messageduring the second timer.
 22. The method of claim 18, wherein at least apart of the data message is received from the second device, in responseto a second request to send message, before transmitting a second clearto send message.
 23. The method of claim 18, wherein the data messagecomprises information indicating a duration of the second timer.
 24. Themethod of claim 23, further comprising: remaining idle during theduration of the second timer in response to receiving the data message.25. The method of claim 18, wherein the second timer is longer than thefirst timer.
 26. The method of claim 18, wherein the data messagecomprises a second request to send message.
 27. An apparatus forwireless communication, in a system comprising: a processor; memory inelectronic communication with the processor; and instructions stored inthe memory and operable, when executed by the processor, cause theapparatus to: determine a first timer based at least in part on aduration for transmitting a first request to send message and a durationfor receiving a clear to send message; transmit the first request tosend message associated with the first timer; and transmit a datamessage having a second timer different from the first timer, the datamessage associated with a data transmission opportunity for theapparatus.
 28. The apparatus of claim 27, wherein the instructions whenexecuted by the processor further cause the apparatus to: receive theclear to send message before an expiration of the first timer based atleast in part on the first request to send message.
 29. The apparatus ofclaim 28, wherein transmitting the data message having the second timeris in response to receiving the clear to send message.
 30. An apparatusfor wireless communication, in a system comprising: a processor; memoryin electronic communication with the processor; and instructions storedin the memory and operable, when executed by the processor, cause theapparatus to: receive a request to send message having a first timerbased at least in part on a duration for receiving the request to sendmessage and a duration for transmitting a clear to send message; andreceive a data message having a second timer different from the firsttimer, the data message associated with a data transmission opportunityfor a second apparatus.
 31. The apparatus of claim 30, wherein theinstructions when executed by the processor further cause the apparatusto: transmit the clear to send message before an expiration of the firsttimer based at least in part on the request to send message.